07-14 HARLEY FLSTC: Kuryakyn Spun Blade Spinning Axle Caps Reminiscent of the great Mustang fighter planes, these spinning blades give the illusion of flight. The chrome-plated ABS blades start to spin when the bike reaches about 25 MPH. The Spun Blades - with Pointed Center Cap - add an additional cool factor to your bike. Sold as a pair. Note: Kuryakyn part number: 1234.